Figure 3.

SegNet architecture. Numbers on top and the left bottom corner of each tensor indicate number of channels/filters and its height and width respectively. Although this network is similar to the U-Net described previously, the network does not contain any skip connections which copy tensors from the encoding steps to the decoding steps. Arrows are color-coded as follows: blue: convolution with (3, 3) filter size, ReLU activation, green: up-convolution with a (2, 2) kernel using max pooling indices from the encoding layers, red: max pooling with a (2, 2) kernel, pink: (1, 1) convolution with sigmoid activation.